Send JSON Object to PHP on AJAX Success - php

Question

In my Controller I've have an array $data whose var dump is as follows:
array
'urls' =>
array
0 =>
array
'link_id' => string '1' (length=1)
'link_name' => string 'http://www.nytimes.com' (length=22)
'words' =>
array
0 =>
array
'keyword_id' => string '1' (length=1)
'keyword' => string 'republican' (length=10)
Array Structure:
$ data will have urls and words only but they can have multiple values. Both will not have the same cardinality.
Then I encode it as echo json_encode($data); in displayData and send this to ajax. displayData needs no POST data. The ajax request made in the View is as follows:
$.ajax({
url:"http://localhost/codeigniter/SiteController3/displayData",
success: function(response){
alert(response);
$("#user_data").html(response);
},
dataType:"json"
})
I want to access the response in my 'View' so that I can
perform json_decode($response, true) and get the associative array.
There is a chunk of code which renders this data in tabular format by
looping on the array. And before this code I want to get the
associative array.
I tried using $.getJSON instead of $.ajax but no solution. Also
tried $.each function, but on alert only getting undefined. Did
JSON.stringify which on alert displayed the JSON but not able to
send it to PHP code.
EDIT:
#fragmentedreality's answer
The content-type inconsistency is solved using the answer. But how can I access the response received on success of AJAX in html body of my View which has a chunk of PHP code for displaying data in tabular format ?
Solution:
Check my answer below.

Answer 1

Add
header('content-type: application/json');
to your controller (before the echo) to set the correct mime-type for you application's response.

Answer 2

Finally I dropped the JSON approach. I added the following line in displayData method of the Controller:
$this->load->view('data_processing', $data);
The data_processing.php is a new View that generates the HTML table I wanted to display. The response of this View is loaded in my original View by the following AJAX request:
$.ajax
({
url: "http://localhost/codeigniter/SiteController3/displayData",
}).done(function(data)
{
console.log(data);
$('#user_data').html(data);
}